For me, it is far less crucial to have start/due dates for my tasks on my blackberry than it is in Outlook. In other words - I like having them stored on my phone for reference, but I primarily manage my tasks through Outlook and complete a majority of them while at my computer.
Because intellisync fills these dates with random garbage, I've never had the ability to organize by start/due date in Outlook - something that I find quite useful with as many tasks as I have (GTD users know what I mean).
After searching through intellisync settings, I found that I could modify the field map to exclude only that data from intellisync. In this way tasks, are still kept updated on both devices, however there are no start/due dates for tasks on my blackberry.
Although I don't have the dates in the blackberry, intellisync no longer F's with my data in Outlook - a less than perfect solution, but a solution nonetheless. For those of you who are interested (Desktop Manager V4.2.2.14, Outlook 2003):
-Fist go through your task list in Outlook and reset all start/due dates to "none"
-Synchronize your devices using Desktop Manager (do this only once because a second sync will create garbage again) At this point both devices should be clean of garbage
-Under "Desktop Manager" select "Synchronize"
-Under the "Configuration" tab, select the "Configure Sync..." button
-Highlight "Tasks" and click the "Configure" drop-down menu
-Choose "Advanced Settings"
-Click the "Field Mapping" button and select "Ok" in the popup
-Deselect the arrow between "Due Date" and "Due Date"
-Deselect the arrow between "Due Time" and "Start Date"
-Click "Ok"
-Click "Ok"
-Click "Ok"
-Click "Close"
-Go to Outlook and add start/due date data as it applies to the particular tasks
-Synchronize at will - you shouldn't have any more problems with trash.
Enjoy

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